ABS (anti-lock braking systems) can experience situational problems when an ABS equipped vehicle is operated in reverse. This is due in part to the conventional “front-loading-bias” of typical automotive braking designs (i.e. front brakes by design, apply greater braking force (higher pressure) than the rear brakes—to compensate for the fact that front tires are much more likely to be heavily loaded during stops from a forward direction of vehicle travel). However, when applying brakes to slow the rearward travel of the vehicle, the front tires may lock up (because during reverse operation most of the vehicle “weight” has transferred to the rear wheels). If the ABS can't detect that the vehicle is travelling in reverse under such apparent “front wheel locking” conditions, then a driver's ability to deploy the required degree of braking is impeded, (i.e. the action of the ABS-controlled brake pedal resists depression and pulsates rapidly), and on steep inclines the vehicle speed can actually increase uncontrollably due to the lack of adequate braking to counter gravitational acceleration. One solution to this problem is disclosed in U.S. Pat. No. 5,267,166, which teaches utilizing vehicle speed, longitudinal acceleration and gravitational acceleration data to control ABS operations and to thereby militate against such problems when the vehicle is being operated in reverse.
This ABS related problem although distressing, tends to arise only in relatively rare (and often relatively innocuous) circumstances.
A far more problematic issue is that the societal costs of accidents arising out of operating vehicles in reverse generally, are entirely disproportionate, and only very rarely have anything to do with the aforementioned ABS problem.
SwissRE Commercial Insurance has published an article which reveals that: “millions of miles are driven each year and most of these miles are driven going forward. Although the majority of accidents occur while vehicles are going forward, approximately 30 percent of all accidents occur when vehicles are moving in reverse. Based on the high frequency of these accidents and the facts that all backing accidents are often preventable, emphasis must be placed on safe backing procedures. Accidents that occur when a vehicle is going in reverse are costly to companies. While the most frequent of claims involve property damage, bodily injury to individuals occurs as well. The element of risk resulting in bodily injury is ever present when backing any vehicle. This is a major factor when considering why the total cost of backing accidents is so high”.
Accordingly, managing all aspects of how vehicles are operated in reverse remains an important social and technological issue.